Tobacco products and method of making



Jan. 22, 1957 L. J. NOVAK Filed Feb. 11, 1955 AQUEOUS DEX TRAN CA RBOXYMETHYL COMM/NU TED TOBA C00 PLAsr/c MASS BLEND/N6 T0 SHAPING 0F PLASTIC MA SS DRY/N6 0F SHAPED MASS TOBA cco PRODUCT COMPRISING CARBOX YME TH YL DEX TRAN BINDER INVENTOR L E0 J. N 0 VA K ATTORNEYS United States Patent 2,778,753 TOBACCO Pnonuors AND METHOD or MAKING Leo J. Novak', Dayton, Ohio, assignor to The Commonwealth Engineering Company of Ohio, Dayton, Ohio, a corporation of Ohio i Application February 11, 1955,.SerialNo. 487,699

19 Claims. (Cl. 131-47 This invention relates to tobacco products and more particularly to products comprising. tobacco in comminuted or particulate form and adapted for smoking.

The manufacture of cigars is quite complex. Inmaking even low-price cigars, for example, it is not unusual for some fifteen to twenty different types and grades of tobacco to be blended together, and a large proportion of the work is done by hand, which. increases the cost and slows up production. The same problems are met in making cigarettes and pipe tobacco.

. An object of this invention is to provide improvements in the blending of tobaccos.

Another object is to provide an improved bonding agent for particles of tobacco and such adjuvants. as flavoring agents, combustion catalysts and adsorbents. as may be mixed therewith.

A further object is to simplify the making of tobacco products. Those and other objects of the invention are accomplished by incorporating with the comminuted or particulate tobacco, as binder therefor, carboxymethyl dextran.

In practicing the invention, leaf tobacco that has been treated in the usual way, that is by drying, curing, sweat-- ing, fermenting, aging and similar treatments, and then comminuted in any of the usual types of grinders or pulveriz'ers to particles passing through a 2'0-mesh screen, and a substantial portion of which are of a size to pass through a 4'0'-mesh screen, is thoroughly mixed with a viscous aqueous solution or gel of carboxymethyl dex tran to obtain a plastic mass in which, if diiierent grades and/or types of tobaccos are present, these are blended to a homogeneous, uniform product. The plastic mass of tobacco is rolled out into sheets or otherwise pressed or formed into desired shapes, e. g.,, extruded as a rod or ribbon and the water is evaporated, leaving a coherent tobacco product.

The process is illustrated diagrammatically in the accompanying flowsheet.

The amount of the aqueous solution or gel comprising carboxymethyl dextran mixed with the comminuted tobacco is just sufficient to form a workable plastic mass. Because of the extraordinary water-imbibing and waterthickening power of carboxymethyl dextran, smaller.

amounts of the dextran ether accomplish this objective than are required for other binders that have been proposed for this use in the prior art. In general, one to three parts by weight of aqueous 3% to'6% carboxymethyl dextran solution or gell to one part of commi-f nuted tobacco yields a mass of the desired consistency and workability. The carboxymethyl dextran may constitute from about 2 to 4.5% of the finished product. a

The carboxymethyl dextran facilitates blending of the various types and grades of tobacco and of the tobacco "ice stantially tasteless and odorless carboxymeth-yldextran. Carboxymethyl. dextran may be. prepared asdescribed in the pending application. of Leov J. Novak et al.,.Serial No. 346,016, filed March 31, l953. Briefly,.the selected dextran and a carboxymethylating agent. are reacted together in an: aqueous alkaline. medium, the carboxymethylgroups being substituted for one or more. .hydroxyl groups in the dextran molecule. Suitable carboxymethylating agents are. ehloracetic acid, sodium chloracetate or chloracetamide. "The reaction may be carriedv out in an aqueous solutionvv of. a strong. alkali metal hydroxide such as sodium, potassium. or lithium hy-- droxide. The ether may be obtained by reactingthe dextran in aqueous solution or suspension with. an. excess of sodium or potassium. hydroxide at a. temperature. of. 50 C. to I00 C. for a time ranging. from about. ten. minutes totwo hours. The molar ratio of sodium or potassium chloracetate to. dextran may be between 25.1 and 12:1, the molar ratio of sodium or potassium. hydroxide between 5:1 and 15:1,. and the. molar ratio of water to-dextran between 70: I and :1. The resulting. ethers have a D. 8. (degree of substitution or average. number of carbo'xymethyl groups per anhydroglucopyranosidic unit), of less than 1:0 up to 3:0,. say 0.5 to 3.0.

The reaction productis a viscous mass comprising the. sodium or potassium salt of the ether, which. may be precipitated by adding any water-miscible alcohol or ketone, such as methyl, ethyl, propyl, isopropyl or t. butyl alcohol, or acetone, to the crude. reaction, mass.

The free' ether maybe recovered by mixing the salt with water, acidifying, to pH about 2.0-3.0, and precipitati'ng the ether by'means of awater-miscible alcohol or ketone. The pH of 2.0-3.0 is not. critical and: the precipitation can. be efiected at other pH values. The dextran may be synthesized fromv sucrose by appropri'ate microorganisms such as. those of the. Leucmtostoc mesenteroides or L. dextranicum types or their enzymes, and may be the native gum. separated from. the. fermentate and having, a very high molecular weight, or a lower molecular weight dextran resulting. from hydrolysis of the native product. In general, the molecular weight of the dextran may be between 2000 and that of the native product. 7' i The carboxymethyl ether may contain from 0.5 to 3.0 carboxymethyl groups per A. G. U. aqueous solutions or gels of the carboxyrnethyl ether derived. from micro biologically produced, high; molecular weight. watensol uble native. dextran such as. native. L. m.. B-5 l2v dextran, and containing. an average. of about 1.0. carboxymethylgroup .per A. G. U. may be preferred. because. of the,

salt formed as intermediate in the production of the carboxymethyl dextran may be used, also, with satis'v factory results.

The highly viscous aqueous solutions or gels of. the

carboxymethyl dextrans or salts permit the finely divided tobacco to be worked into a cohesive pliable massthat can be sheeted or rolled without difficulty and on removal' of the water the. dextran ether or salt remains as a film on the particles to bind them into. a cohesive mas which does not crumble readily.

v The dextran ether and its salt have advantages over.

cellulose derivatives for the. present purposes. One advantage is the" relative ease of purifying thestart'ing dextran and of obtainingjthe derivatives in pure form. for optimurrr'smokingcompatibility of the etheror salt" The plastic mass comprising the. carboxywith the tobacco. Another advantage is that combustion of dextran does not give rise to the carcinogenic hydrocarbon benzpyrene which has been found to be a combustion product of cellulose. A further advantage is that the carboxymethyl dextrans produce aqueous solutions or gels of a given thickness or viscosity in smaller concentrations than any of the available carboxymethyl celluloses or other water-soluble cellulose derivatives. For example, the carboxymethyl ether of native L. m. B-512 dextran having an average D. S. of about 1.0 thickens water to an extent that is only attained with commercially available carboxymethyl celluloses when from 3 to 4 times the amount of the cellulose ethers are used.

It is conventional to include 1% to 2% by weight of bentonite or like mineral in tobacco products for the purpose of improving the coherency of the final product. The bentonite is not required for the purpose when carboxymethyl dextran binder is used, although it may be desirable to include it for assisting in absorbing and filtering out tarry constituents and alkaloids of the tobacco smoke drawn through the unsmoked portion of the cigar or cigarette.

Harmless plasticizers such as glycerine may be included for increasing the flexibility of the sheeted product, although the need for plasticizers is decreased when the dextran ether or its salt is used.

The following examples are illustrative of specific embodiments of the invention, it being understood that these examples are not intended as limitative.

Example I A mixture of water and 0.5% by weight of carboxymethyl dextran derived from L. m. B-512 native dextran and having a D. S. of about 1.1 is prepared and mixed with a blend of 40 parts Wisconsin binder tobacco, 44 parts of Pennsylvania tobacco and 16 parts of Havana tobacco comminuted to a particle size of to mesh. The resulting plastic mass is extruded through a slit 2 inches long and inch Wide. This extruded ribbon of tobacco paste is deposited on a moving band of Wire cloth and dried on the band by means of air at C. The drying is continued until the ribbon has a moisture content of 19%20%, after which it is cut into shreds of the size for cigarettes. The cigarette is made in the usual way.

Example II Air-dried Pennsylvania leaf tobacco comminuted to a particle size of 20 to 40 mesh is thoroughly mixed with a mixture of water and 0.1% by weight of the sodium salt' of the carboxymethyl ether of Example I. The pasty, plastic but relatively dry-appearing mass is placed on plate glass and covered with a sheet of Wax paper. The sheet is pressed out by rolling between the wax paper and plate glass into a layer about inch thick. The wax paper is removed and the plastic layer on the glass is transferred to a drying chamber and dried by circulating air heated to 50 C. The drying is continued until the product has a moisture content of about 16%, after which it is taken from the drier, put up in the form of a cigar and provided with a thin wrapper of Sumatra tobacco.

Carboxymethyl ethers of other native and hydrolyzed dextrans and having a D. S. of 0.5 to 3.0, are also efiective as binders for the tobacco particles, as are their alkali metal salts. v

Additives which are commonly used to impart various properties to the tobacco products may be mixed with the comminuted tobacco or with the plastic mass comprising the latter and the carboxymethyl dextran. Such additives include flavoring agents and substances which have a favorable effect on the texture and porosity of the product such as diatomaceous earth. Use of the carboxymethyl dextran as binder and blending agent for the tobaccos results in a homogeneous product which can be readily reproduced, has the same burning characteristics and taste at all portions of the product, and which is economical in that, the tobacco particles being bonded, the coherent products are easy to shape and handle.

Since it is apparent that various changes and modifications may be made in practicing the invention without departing from the spirit and scope thereof, it will be understood that it is not intended to limit the invention except as defined in the appended claims.

What is claimed is:

l. A tobacco product adapted to be smoked and comprising tobacco particles bonded together by a substance selected from the group consisting of carboxymethyl dextran containing an average, of 0.5 to 3.0 carboxymethyl per groups per anhydroglucose unit and alkali metal salts thereof.

2. A tobacco product adapted to be smoked comprising tobacco particles bonded together by carboxymethyl dextran containing an average 05 0.5 to 3.0 carboxymethyl groups per anhydroglucose unit.

3. A tobacco product adapted to be smoked comprising tobacco particles bonded together by the sodium salt of carboxymethyl dextran containing an average of 0.5 to 3.0 carboxymethyl groups per anhydroglucose unit.

4. A substantially homogeneous tobacco product adapted to be smoked comprising a blend of different tobaccos in particulate form, the particles being bonded together by a substance selected from the group consisting of carboxyrnethyl dextran containing an average of 0.5 to 3.0 carboxymethyl groups per anhydroglucose unit, and alkali metal salts thereof.

5. A tobacco product according to claim 4, characterized in that theblended tobaccos are of different types.

6. A tobacco product according to claim 4, characterized in that the blended tobaccos are of ditferent grades.

7. A tobacco product according to claim 4, characterized in that the blended tobaccos are of different types and grades.

8. A cigar comprising particles of tobacco bonded together by carboxymethyl dextran containing an average of 0.5 to 3.0 carboxymethyl groups per anhydroglucose unit.

9. A cigarette comprising particles of tobacco bonded together by carboxymethyl dextran containing an average of 0.5 to 3.0 carboxyrnethyl groups per anhydroglucose unit.

10. A tobacco product adapted to be smoked comprising particles of tobacco bonded together by a carboxymethyl ether of native, high molecular weight, microbiologically produced Water-soluble dextran containing an average of about 1.0 carboxymethyl group per anhydroglycopyranosidic unit.

11. The method of making tobacco products adapted to be smoked which comprises mixing particulate tobacco with a viscous to gel-like mixture of water and a substance selected from the group consisting of carboxymethyl dextran containing an average of 0.5 to 3.0 carboxymethyl groups per anhydroglucose unit and alkali metal salts thereof to obtain a plastic mass, forming the mass into the desired shape for smoking, and drying the shaped product to obtain a shaped tobacco product in which the tobacco particles are bonded together by the carboxymethyl dextran or salt.

12. Themethod according to claim 11, in which par ticles of diflerent tobaccos are blended into a substantially homogeneous mass by mixing with the mixture of Water and carboxymethyl dextran or salt.

13. The method according to claim l2, in whichthc tobaccos blended to a substantially homogeneous mass are of different types.

14. The method according to claim 12, in which the tobaccos' blended to a substantially homogeneous mass are ofdifierent grades.

15. The method according to claim 12, in which the tobaccos blended to a substantially homogeneous mass are of different types and grades.

16. The method of making an improved cigar which comprises mixing particulate tobacco with a viscous to gel-like mixture of Water and a substance selected from the group consisting of carboxymethyl dextran contain ing an average of 0.5 to 3.0 carboxymethyl groups per anhydroglucose unit and alkali metal salts thereof to ob- V tain a plastic mass, sheeting the mass, rolling the sheet to obtain a cigar, and drying the rolled product to obtain a cigar in which the particles are bonded together by the carboxyinethyl dextran or salt.

17. The method according to claim 16, characterized in that different 'tobaccos are mixed with the mixture of water and carboxymethyl dextran or salt and blended into a homogeneous plastic mass as a result of the mixing.

18. The method of making an impnovedl cigarette which comprises mixing particulate tobacco with a vis' cons to gel-like mixture of water and a sub-stance selected from the group consisting of carboxymethyl dextran containing an average of 0.5 to 3.0 carboxyrnethyl groups per anhydroglucose unit and alkali met-a1 salts thereof to obtain a plastic mass, extruding the mass in the shape of ribbon, drying the ribbon, shredding the ribbon and forming the shreds into a cigarette in which the tobacco particles are bonded together by the carboxymethyl dextran or salt.

l9. The method according to claim 18, characterized in that different tobaccos are mixed with the mixture of water and carboxymethyl dextran or salt and blended into a homogeneous plastic mass as a result of the mixing.

References Cited in the file of this patent UNITED STATES PATENTS I 1,954,109 Whitaker Apr. 10, 1934 2,089,217 Mahoney Aug. 10, 1937 2,371,389 Goepp Mar. 13, 1945 2,602,082 Owen May 1, 1950 2,706,695 Frankenburg Apr. 19, 1955 OTHER REFERENCES Nature Magazine: Dextran and its Applications, Feb. 6, 1954, pages 235 to 237, inclusive, cited. 

1. A TOBACCO PRODUCT ADAPTED TO BE SMOKED AND COMPRISING TOBACCO PARTICLES BONDED TOGETHER BY A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF CARBOXYMETHYL DEXTRAN CONTAINING AN AVERAGE OF 0.5 TO 3.0 CARBOXYMETHYL PER GROUPS PER ANHYDROGLUCOSE UNIT AND ALKALI METAL SALTS THEREOF. 